Chmielewski Medical Clinic measures its activity in terms of patient-visits. Last month, the budgeted level of activity was 1,560 patient-visits and the actual level of activity was 1,530 patient-visits. The clinic's director budgets for variable overhead costs of $1.10 per patient-visit and fixed overhead costs of $19,900 per month. The actual variable overhead cost last month was $1,400 and the actual fixed overhead cost was $21,720. In the clinic's flexible budget performance report for last month, what would have been the variance for the total overhead cost?